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101.
Richard L. Venezky 《Computers and the Humanities》1988,22(4):285-291
The Dictionary of Old English computing systems have provided access since the 1970s to a database of approximately three million running words. These systems, designed for a variety of machines and written in a variety of languages, have until recently been planned with computing center billing algorithms in mind. With personal workstations emphasis has shifted to building more elegant user interfaces and to providing the entire DOE database to editors around the world. While the shift from sequential files to random access files and the provision of extensive development tools have changed some of the design process, error checking and protection of the database against accidental intrusion have remained as central issues.Richard L. Venezky is Unidel Professor of Educational Studies and professor of Computer and Information Sciences at the University of Delaware. He was formerly professor and chair of Computer Sciences at the University of Wisconsin. His research interests include writing systems, literacy, knowledge representation, and computer-assisted instruction. Among his recent publications are The Subtle Danger: Reflections on the Literacy Abilities of America's Young Adults (Princeton, NJ: ETS, 1987), and Steps Towards a Modern History of American Reading Instruction (Review of Research in Education, 1986, vol. 13, 129–70). 相似文献
102.
When a set of rules generates (conflicting) values for a virtual attribute of some tuple, the system must resolve the inconsistency and decide on a unique value that is assigned to that attribute. In most current systems, the conflict is resolved based on criteria that choose one of the rules in the conflicting set and use the value that it generated. There are several applications, however, where inconsistencies of the above form arise, whose semantics demand a different form of resolution. We propose a general framework for the study of the conflict resolution problem, and suggest a variety of resolution criteria, which collectively subsume all previously known solutions. With several new criteria being introduced, the semantics of several applications are captured more accurately than in the past. We discuss how conflict resolution criteria can be specified at the schema or the rule-module level. Finally, we suggest some implementation techniques based on rule indexing, which allow conflicts to be resolved efficiently at compile time, so that at run time only a single rule is processed.An earlier version of this work appeared under the title Conflict Resolution of Rules Assigning Values to Virtual Attributes inProceedings of the 1989 ACM-Sigmod Conference, Portland, OR, June 1989, pp. 205–214.Partially supported by the National Science Foundation under Grant IRI-9157368 (PYI Award) and by grants from DEC, HP, and AT&T.Partially supported by the National Science Foundation under Grant IRI-9057573 (PYI Award), IBM, DEC, and the University of Maryland Institute for Advanced Computer Studies (UMIACS). 相似文献
103.
传统SQL数据库在管理大数据、性能和扩展性等方面的不足使得其不能胜任如大规模数据挖掘、商务智能及社交网络等应用场景,而NoSQL数据库由于其在上述应用领域优良的特性近年来得到很快发展。本文在分析现有开源NoSQL数据库产品Kyoto Cabinet和Tair的不足基础上,设计并实现了一个高性能的Key/Value数据库XDB。XDB分段流水并发处理Key/Value请求,并采用一致性算法保证在并发环境中对Key/Value记录读写的相关性,在随机写入和顺序写入实验中,相比于Kyoto Cabinet,XDB的性能分别提高6倍和15倍。 相似文献
104.
自微软公司推出SQL Server关系数据库管理系统以来,其在越来越多的电子商务网站和企业信息平台中得以广泛使用。然而与之相关的信息安全问题也日益凸现和受到用户的密切关注。因此,为了保护SQL Server数据库避免来自各种途径的安全威胁,保障信息的安全,本文对其安全机制、安全策略和保障其安全的管理策略进行了探讨,提出了相应的解决措施和办法,以供参考。 相似文献
105.
刘旭东 《计算机光盘软件与应用》2012,(4):35+39
本文主要是介绍利用Excel的VBA与ADO和SQL技术相结合来存取外部数据库,使得数据管理更加有效,为开发各种应用系统提供方法和依据。 相似文献
106.
徐晓明 《计算机光盘软件与应用》2012,(1):127-128
检验标准管理系统从工作实际出发,采用VisualBasic来制作交互介面,MicrosoftAccess作为后台支持的数据库来管理数据信息,从而实现产品质量检验机构的检验标准管理自动化。该系统是从服务客户和检验人员的角度出发,本着为客户提供准确、快捷、方便服务和更好管理本单位检验标准、方便检验人员使用的原则,可使检验机构大量的检验标准信息得以快捷管理,缩短了客户办理检验业务的时间,以及检验人员检验过程中快速查询使用检验标准的相关信息。本管理系统主要完成:对检验标准中数据的增加、数据的删除、数据的查询和数据的浏览。 相似文献
107.
基于特征的派生式车身覆盖件冲压CAPP的研究 总被引:6,自引:0,他引:6
本文介绍了一种基于特征的派生式车身覆盖件冲压工艺CAPP系统。通过建立特征模型,引入成组技术,建立工艺数据库,系统的功能得以实现。该系统保证了车身开发中CIMS的信息集成。 相似文献
108.
Anna Iwaniak Damir Mogut Piotr Minkiewicz Justyna ulewska Magorzata Darewicz 《International journal of molecular sciences》2021,22(6)
In silico and in vitro methods were used to analyze ACE- and DPP-IV-inhibiting potential of Gouda cheese with a modified content of β-casein. Firstly, the BIOPEP-UWM database was used to predict the presence of ACE and DPP-IV inhibitors in casein sequences. Then, the following Gouda cheeses were produced: with decreased, increased, and normative content of β-casein after 1 and 60 days of ripening each (six variants in total). Finally, determination of the ACE/DPP-IV-inhibitory activity and the identification of peptides in respective Gouda-derived water-soluble extracts were carried out. The identification analyses were supported with in silico calculations, i.e., heatmaps and quantitative parameters. All Gouda variants exhibited comparable ACE inhibition, whereas DPP-IV inhibition was more diversified among the samples. The samples derived from Gouda with the increased content of β-casein (both stages of ripening) had the highest DPP-IV-inhibiting potency compared to the same samples measured for ACE inhibition. Regardless of the results concerning ACE and DPP-IV inhibition among the cheese samples, the heatmap showed that the latter bioactivity was predominant in all Gouda variants, presumably because it was based on the qualitative approach (i.e., peptide presence in the sample). Our heatmap did not include the bioactivity of a single peptide as well as its quantity in the sample. In turn, the quantitative parameters showed that the best sources of ACE/DPP-IV inhibitors were all Gouda-derived extracts obtained after 60 days of the ripening. Although our protocol was efficient in showing some regularities among Gouda cheese variants, in vivo studies are recommended for more extensive investigations of this subject. 相似文献
109.
110.
Solid Edge的数据库开发技术在族类零件开发中的应用 总被引:2,自引:0,他引:2
用Solid Edge的数据库开发技术对族类零件进行开发,采用基于Jet数据库引擎的AD0数据控件访问方法和各种数据绑定控件并编写应用程序,对零件进行有效的管理并实现参数化设计,为后续的CAX和并行工程提供数据模型。 相似文献